Despite all the rumors about the SAS, especially the weapons they use, the SAS don't have their weapons customized, nor do they use their personal weapons on missions. All SAS soldiers use standard weapons as this make life easier, less complicated.

HK MP5 Submachine gun:
A highly reliable CQB (close quarter battle)weapon. The MP5 uses a 9mm caliber round, this combined with the fact that it uses closed bolt position during all forms of fire makes this weapon highly controllable, even with its high rate of fire.
The other advantage of this weapon is the fact that it has a Collapsible stock, and its light weight make it easy to Maneuver in tight spaces. The MP5 is used in more than 50 nations as its law enforcement units.

MP5 SD submachine gun:
This is basically the same as the above MP5, with the exception that it is fitted with a suppressor, specifically for sound and flash.
The removable sound suppressor is integrated into the design. The MP5SD uses a integral aluminum or optional wet technology stainless steel suppressor, and it does not require the use of subsonic ammunition for effective sound reduction.

SA 80:
This is a more powerful 5.56mm caliber weapon., fitted with a high performance optical sight, with a 4x magnification.
The added advantage of this weapon is that it has very little recoil compared to other weapons of the same caliber and can fire 650-800 rounds/minute, at an effective range of 400m. The weapon is designed to be simple to dismantle without special tools.

M72- Light Anti Tank Weapon (LAW):
This is a throw away type rocket. The rocket is made up of a 66mm HEAT warhead. Attached to the nozezle of the warhead are six spring loaded fins, which are folded when the warhead is in the firing tube. After firing the fins are deployed to stabilize the rocket in flight.
The M72 has a muzzle velocity of 145m/s, and a range of up to 1000m and can penetrate 305mm of armour

L2 Grenade:
A highly explosive anti personal grenade, based on the US M26 grenade. It has a delay of 4,4s and a effective radius of 10m.

Flash Bang:
This is a very effective tool when it comes to hostage rescue. It emmits a Vivid Flash and an extremely lound bang, hence the name "flash bang". The idea is to completely disorientate the enemy without killing him, thus giving the SAS time to infiltrate a room, giving them the extra seconds they may need to neutrilze a terrorist, and safely rescue a hostage

The SAS are also trained in using foreign weapons, for obvious reasons. If they are supposed to be doing a covert operation, in some strange land they will use whatever weapons is preferred by the enemy, such as the AK 47, to avoid looking Suspicious.

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